WP_Site_Health::test_php_extension_availability() WordPress Method

	private function test_php_extension_availability( $extension_name = null, $function_name = null, $constant_name = null, $class_name = null ) {
		// If no extension or function is passed, claim to fail testing, as we have nothing to test against.
		if ( ! $extension_name && ! $function_name && ! $constant_name && ! $class_name ) {
			return false;
		}

		if ( $extension_name && ! extension_loaded( $extension_name ) ) {
			return false;
		}

		if ( $function_name && ! function_exists( $function_name ) ) {
			return false;
		}

		if ( $constant_name && ! defined( $constant_name ) ) {
			return false;
		}

		if ( $class_name && ! class_exists( $class_name ) ) {
			return false;
		}

		return true;
	}